Question

In my app, i have admin subfolder, and controller there, and method:

class Admin::UserGroupsController < ApplicationController
  def index
    @pre_usergroups = UserGroup.all
    @user_groups = Kaminari.paginate_array(@pre_usergroups).page(params[:page]).per(50)
    render :layout => 'admin'
  end
end

route:

namespace :admin do
resources :user_groups
end

and model (not in subdirectory admin):

class UserGroup < ActiveRecord::Base
  attr_accessible :group_id, :user_id
  belongs_to :group
  belongs_to :user
  validates :user_id, :presence => {:message =>  I18n.t(:user_not_chosen)}
  validates :group_id, :presence => {:message =>  I18n.t(:group_not_chosen)}


  def get_group_name(id)
    @gr = Group.find(id)
    @gr.name
  end

  def get_user_name(id)
    @user = User.find(id)
    @user.email
  end
end

Also i didn’t see validation message’s and it’s working…. it skip validation:

and view:

%table.table.table-striped
  %tr
    %th
      Название группы:
    %th
      Пользователь:  
  -@user_groups.each do |u|
    %tr  
      %td
        = u.get_group_name(group_id)
      %td
        = u.user_id

But why i get

 undefined local variable or method `group_id' for #<#<Class:0xb352734>:0xab437dc>

So i didn’t go to method in model…
How can i access model method?

Answer 1

as stated in the error group_id is not defined which is true.
You should be calling it as follows:

= u.get_group_name(u.group_id)

because group_id is an attribute of the UserGroup object

However, I don’t see why you are making the methods get_group_name and get_user_name, why don’t you just use u.group.name and u.user.email?